Which patients with moderate hypoxemia benefit from long-term oxygen therapy? Ways forward

Magnus Ekström,1 Thomas Ringbaek2 1Department of Respiratory Medicine and Allergology, Skåne University Hospital, Lund University, Lund, Sweden; 2Respiratory Department, Hvidovre Hospital, Copenhagen, Denmark Abstract: Long-term oxygen therapy (LTOT) improves prognosis in patients with COPD and chronic severe hypoxemia. The efficacy in moderate hypoxemia (tension of arterial oxygen; on air, 7.4−8.0 kPa) was questioned by a recent large trial. We reviewed the evidence to date (five randomized trials; 1,191 participants, all with COPD). Based on the current evidence, the survival time may be improved in patients with moderate hypoxemia with secondary polycythemia or right-sided heart failure, but not in the absence of these signs. Clinically, LTOT is not indicated in moderate hypoxemia except in the few patients with polycythemia or signs of right-sided heart failure, which may reflect more chronic and severe hypoxemia. Keywords: survival, oxygen therapy, hypoxemia, COP

Quantify and account for field reference errors in forest remote sensing studies

Field inventoried data are often used as references (ground truth) in forest remote sensing studies. However, the reference values are affected by various kinds of errors, which tend to make the reported accuracies of the remote sensing-based predictions worse than they are. The more accurate the remote sensing techniques are becoming, the more pronounced this problem will be. This paper addresses the impact of uncertainties in field reference data due to measurement errors, model errors, and position errors when evaluating the accuracy of biomass predictions from airborne laser scanning at plot level. We present novel theoretical analysis methods that take the interactions of the error sources into account. Further, an error characterization model (ECM) is used to describe the error structure of the remote sensing-based predictions, and we show how the parameters of the ECM can be adjusted when field references contain errors. We also show how root mean square error (RMSE) estimates can be adjusted. Based on data from Scandinavian forests, we conclude that the field reference errors have an impact on the remote sensing-based predictions. By accounting for these errors the RMSE of the remote sensing-based predictions was reduced by 6-18%. The most influential sources of error in the field references were found to be the residual errors of the allometric biomass model and the field plot position errors. Together, these two sources accounted for 97% of the variance while measurement errors and biomass model parameter uncertainties were negligible in our study

The independent association of overweight and obesity with breathlessness in adults: a cross-sectional, population-based study

Obesity is an independent risk factor for chronic breathlessness and should be assessed in people with this symptom

One evidence base; three stories: do opioids relieve chronic breathlessness?

Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/. The efficacy of low-dose systemic opioids for chronic breathlessness was questioned by the recent Cochrane review by Barnes et al We examined the reasons for this conflicting finding and re-evaluated the efficacy of systemic opioids. Compared with previous meta-analyses, Barnes et al reported a smaller effect and lower precision, but did not account for matched data of crossover trials (11/12 included trials) and added a risk-of-bias criterion (sample size). When re-analysed to account for crossover data, opioids decreased breathlessness (standardised mean differences -0.32; -0.18 to -0.47; I2=44.8%) representing a clinically meaningful reduction of 0.8 points (0-10 numerical rating scale), consistent across meta-analyses

Both deterioration and improvement in activities of daily living are related to falls: a 6-year follow-up of the general elderly population study Good Aging in Skåne.

To determine the relationship between long-term change in activities of daily living (ADL) and falls in the elderly and to identify characteristics of groups at risk for falls

Can variability in the effect of opioids on refractory breathlessness be explained by genetic factors?

© 2015, BMJ Publishing Group. All rights reserved. Objectives: Opioids modulate the perception of breathlessness with a considerable variation in response, with poor correlation between the required opioid dose and symptom severity. The objective of this hypothesis-generating, secondary analysis was to identify candidate single nucleotide polymorphisms (SNP) from those associated with opioid receptors, signalling or pain modulation to identify any related to intensity of breathlessness while on opioids. This can help to inform prospective studies and potentially lead to better tailoring of opioid therapy for refractory breathlessness. Setting: 17 hospice/palliative care services (tertiary services) in 11 European countries. Participants: 2294 people over 18 years of age on regular opioids for pain related to cancer or its treatment. Primary outcome measures: The relationship between morphine dose, breathlessness intensity (European Organisation for Research and Treatment of Cancer Core Quality of Life Questionnaire; EORTCQLQC30 question 8) and 112 candidate SNPs from 25 genes (n=588). Secondary outcome measures: The same measures for people on oxycodone (n=402) or fentanyl (n=429). Results: SNPs not in Hardy-Weinberg equilibrium or with allele frequencies ( < 5%) were removed. Univariate associations between each SNP and breathlessness intensity were determined with Benjamini-Hochberg false discovery rate set at 20%. Multivariable ordinal logistic regression, clustering over country and adjusting for available confounders, was conducted with remaining SNPs. For univariate morphine associations, 1 variant on the 5-hydroxytryptamine type 3B (HTR3B) gene, and 4 on the β-2-arrestin gene (ARRB2) were associated with more intense breathlessness. 1 SNP remained significant in the multivariable model: people with rs7103572 SNP (HTR3B gene; present in 8.4% of the population) were three times more likely to have more intense breathlessness (OR 2.86; 95% CIs 1.46 to 5.62; p=0.002). No associations were seen with fentanyl nor with oxycodone. Conclusions: This large, exploratory study identified 1 biologically plausible SNP that warrants further study in the response of breathlessness to morphine therapy

En marknadsundersökning om regelvirke

Today there is a widespread opinion that the woodmarket and the forest industry are dominated by a traditional way of thinking and not adapted to the customers of today; a lot of products are produced purely on routine. Also, there is a demand for improving the quality of sawn woodproducts. AB Karl Hedin wants to sort this out by increasingly adapt their products to the demands of the market, i.e. through introducing a short wallstud of standard length, "Hedinregeln". At tirst, the wallstud will be produced in lengths of 2,70 m and of guaranteed quality. The small amount of published material on length-adapted building timber has shown to be out of date. Therefore, we have through interviews with companies and questionnaires to private persons tried to tind out what customers of different categories think about the product and what quaiity aspects they evaluate the most when buying construction wood. Also we have found out how customers want to receive information about new and improved wood products and what they think could be improved with "Hedinregeln". The statistic process has been done in Microsoft Excel. After the analysis of the interviews and the questionnaires we split the customers into four groups: private persons, small construction companies, medium-sized construction companies and big construction companies. Different trade patterns could be distinguished. In the results One can see that most people appreciate the intentions to produce new costumer-adapted products. Also, one thinks it is good that the sawmills try to improve the quality of sawed wood. One reason why many companies do not want to buy "Hedinregeln" is that they must keep their construction costs low. They chose instead a lower quaiity to a lower price. Most companies show a sceptical attitude towards the length of "Hedinregeln". The waste one avoids thanks to better quality, appears instead when cutting the studs of the "incorrect" length. Private persons also show a sceptical attitude towards "Hedinregeln" but for completely different reasons. One of the main reasons why private persons go to the timber yards, instead of going to the supermarkets, to shop for wooden products is the possibility to sort timber from packages with timber of different lengths. Often, private persons do not account for their own time at the timber yard, i.e as an important cost. The construction companies have to consider time as a cost. Even if most companies and private persons are sceptical about buying the "Hedinregeln", almost all of them see great advantages with the product. Probably it would facilitate the handling during construction and transport as weIl as lower the costs related to the handling of the product. We have found that the customers are not interested in buying the wallstud. There are same groups that we think could get benefits from buying the holt if one could find a proper way of giving them information as how to use the wallstud. Among others there are small and average small construction companies that would get advantages by using the "Hedinregeln". Big construction companies prefer to pay a bit extra to get the bolts of exactly the right length to get rid of as much handling of the wood as possible. Private persons do not mind spending some extra time sorting out the timber they want. Therefore they are not a target group. Most of the customers agreed that the most important quality aspect is that the wood is straight. The quality aspect "right length" was not so important. More important is that the wood is knotless and without bark. Even the right amount of moisture in the timber is more important than the "right length". Most companies lacked relevant information from the wooden industry. Among the companies who brought the timber from the timber yard themselves, a majority said they got the information by searching at the timber yard or by asking other people in the same business. The most reliable and the mostly appreciated information source is the information from the seller. And it is from the seller that most people want the information.Det finns idag en utbredd uppfattning om att trävarumarknaden och skogsindustrin styrs av ett traditionellt tänkande som inte är anpassat efter dagens kunder och att man tillverkar alltför mycket på rutin. Dessutom finns det krav på en förbättring av kvaliteten hos sågade trävaror. På Karl Hedin vill man komma tillrätta med detta genom att ytterligare anpassa sina produkter efter marknadens krav bl.a. genom att introducera en kortregel av standardlängd, "Hedinregeln". Regeln ska i ett första skede tillverkas i längden 2,70 och vara kvalitetssäkrad. Den lilla mängd publicerat material som finns att tillgå om längdanpassat virke har visat sig föråldrat. Vi har därför genom intervjuer med företag och enkäter till privatpersoner försökt ta reda på hur olika kundkategorier uppfattar produkten samt undersökt vilka kvalitetsaspekter de tittar på när de köper regelvirke. Vi har också fått en inblick i hur de vill ha information om nya produkter och vad de tycker skulle kunna göras bättre med "Hedinregeln". Den statistiska bearbetningen gjordes i Microsoft Excel

Comparing TanDEM-X InSAR Forest Stand Volume Prediction Models Trained Using Field and ALS Data

Remote sensing (RS) techniques have been used for mapping forest variables, such as stem volume (important for forest management activities associated with timber production), over large areas which can be updated more frequently than with field inventory (FI) data. In this study, wall-to-wall TanDEM-X synthetic aperture radar images were used as auxiliary RS data for model-based prediction of stand-level volumes for two models, trained using volumes computed from FI (A) and airborne laser scanning estimations (B), respectively. The models were validated with harvester data available for independent stands. It was observed that the performance of model B was slightly better compared to model A based on adjusted R 2 and root mean squared error values. Therefore, it can be concluded that a completely RS based approach for prediction and mapping of stand volumes would be as promising as a method based on FI data along with being cost- and labour-efficient